Controls for torque converter movable blades



April 19, 1960 B. M EDSALL rAL 2,932,940

CONTROLS FOR TORQUE CONVERTER MOVABLE BLADES Original Filed June 22. 1955 `Inasmuch as the lspeed of United States Patent CONTROLS FOR TORQUE CONVERTER MOVABLE BLADES Bruce M. Edsall, Oak Park, and John B. Richardson, Pleasant Ridge, Mich., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Continuation of application Serial No. 517,156, June 22, 19 This application April 25, 1958, Serial No. `731,587

a maximum torque multiplication angle to a minimum torque multiplication angle.`

In the copending application of Edsall and Moore, Serial No. 353,782, filed May 8, 1953, for Automatic Transmission, the transmission described and illustrated makes use of a torque converter having a pump, iirst and secondturbines and a reaction member or stator. The two turbines are connected to elements of a planetary gear system in order that different stages of drive by the torque converter can be effected. The blades of the reaction member or stator of the torque converter are mounted -for pivotal movement whereby the position thereof relative to the discharge of the second turbine and the entrance of the pump can be changed from a low torque multiplication angle to a high torque multiplication angle, with the possibility of the blades remaining in any intermediate, angular torque requirements of the transmission and the load driven thereby may require. The present invention constitutes an improved control system for determining the angle at which the blades of a reaction member or stator may be positioned at any stage of operation of the torque converter.

In the operation of vehicles employing modern high compression engines that it is sometimes of advantage to increase the speed of the engine when starting the car, particularly at wide throttle openings. For example, with some high compression engines it has been found that if the car is started with the throttle fully open, or nearly so, and if the engine speed is about 1800 r.p.m. when the car starts to move, auto-ignition may occur. If, however, the speed of the engine for wide or full throttle under the same conditions can be increased to 2400 to 2600 r.p.m., auto-ignition is not apt to occur. the engine depends upon the torque ratio of the transmission, an adjustment of the torque ratio of the transmission will permit the engine speed to be increased beyond the auto-ignition range.

An object of the invention is to provide controls for a torque converter of such character that when the converter is operated for starting a vehicle in motion under wide or full throttle control of the engine, the torque converter can be automatically conditioned to accomplish high torque multiplication so that engine speed can be raised.

Another object of the invention is to provide controls for the adjustable blades vof a torque converter reaction member, or stator, which controls operate automatically to provide the degree of torque multiplication in the converter that is demanded by the position of the engine controlling throttle.

Another object of the invention is to provide controls position as the as just described which operate automatically to increase the ytorque multiplication by the converter during idling of the engine to such an extent that so-called creep of the vehicle driven by the torque converter is prevented.

Another object of the invention is to provide controls for the blading of the converter stator which controls automatically operate to condition the blading for maximum torque multiplication upon a full throttle acceleration of the vehicle.

A further object of the invention is to provide controls of such character as to automatically regulate the position of the stator blading to provide intermediate torque multiplication, gradually decreased to minimum torque multiplication during a light throttle acceleration of the vehicle from rest.

A still further object of the invention is to provide controls for torque converter stator blading of such character as to automatically position the blading to obtain a minimum of creep during idling of the engine and which controls function to position the blading in the maximum torque multplication angle with substantially no delay upon full throttle acceleration of the vehicle from rest. i

In carrying out the foregoing and other objects of the invention, it is to be understood that the controls illustrated and described in connection herewith are particularly adapted for, but not limited to, a transmission of the type disclosed by the aforesaid copending application. For this reason illustration has been of only' part of a torque converter and shown associated therewith are certain elements Which are well-known in connection with hydraulically controlled automotive trans-- missions. For the purposesiof this invention, it is necessary only to describe the manner in which the blading of the reaction member or stator of a torque converter can be automatically controlled to provide the torque multiplication in the converter most advantageous to the operation of the converter at any of a plurality of engine throttle openings. The reaction member, or stator, of the torque converter has the blades thereof mounted for pivotal movement about axes extending radially from the hub of the stator. The blades are biased to a low torque multiplication angular position by a spring acting on a piston which receives cranks on blades spindles. The low torque multiplication angle is that position in which a minimum of redirection of oil or other liquid is imparted to the oil passing from a turbine to the converter pump. In addition to the spring biasing means, the blades have their pivotal points so located relative to the entrance and exit ends thereof and are so spaced apart that the liquid in the Working circuit of the torque converter applies a force to the blades tending to move them to the minimum angular position. As the velocity of the liquid being circulated in the converter increases, the force thereof tending to move the blades to the low angle position increases. Consequently to move the blades to a high torque multiplication angmlar position it is necessary to supply a force greater than the spring biasing force and that supplied by the circulation of the liquid in the converter.

The present invention provides controls whereby the blades can be moved to the high torque multiplication angular position automatically when the engine is idling, i.e., when the pump of the converter is rotating at a relatively low speed, whereby the multiplication factor of the converter is increased with an end result that the slip of the converter elements is increased so that the tend-l ency of a vehicle driven by the converter to creep during engine idling is materially reduced if not completely eliminated. These controls operate automatically to cause the blades to be moved to the high torque Amule assess@ time merely to point out that to regulate an oil pressure which increases as the engine throttle is opened, delivering a pressure which may vary from zero to full pump pressure. When the throttle modulator valve 102 isin the position shown in the drawing, it will be evident that oil reaching the bore thereof through the line 100 can pass therefrom into the line 60 which extends to the piston 36 of the converter stator.

The final valve employed in these controls comprises the high speed cut o valve 120 which has lands 122 and 124 of different diameters. The valve 120 is slidable in the stepped bore provided therefor in the valve body. Valve 120 is biased open or to the right by spring 126 and when in this position it completes communication through the bore for oil from pump delivery line 96 to a line 128 which extends to a port in the bore of the throttle modulator valve 102 at which location further progress is arrested so long as valve 102 is in the position shown.

For a complete understanding of the operation of these controls, it is necessary to assign a selected series of values to the various biasing means, but it will be understood that these values are not critical but can be varied for whatever calibration of the system may be considered advantageous. With this in mind, therefore, let it be assumed that the spring 38 is preloaded to exert a force of 10 p.s.i. on piston 36. The spring 86 is preloaded to exert a force of 28 valve 80. Spring 35 p.s.i. on the the throttle valve operates 108 is preloaded to exert a force of throttle modulator valve 102. Spring v126 is so preloaded as to exert a force which will hold the valve 120 in its illustrated position until the governor 70 delivers a pressure thereto through the line 74 which is representative of a predetermined vehicle speed, which for purposes of illustration may be described as 58 m.p.h. With these spring values in mind and with the assumption that the pump 64 delivers a pressure varying from 65 to 130 p.s.i. and that the throttle valve 112 regulates pressure supplied through the line 113 to the throttle modulator valve 102 over a range extending from zero at closed throttle position to pump pressure, or 130 p.s.i., at wide open throttle position.

Idling With the pump 10 of the converter being driven at idling speed, i.e., in the neighborhood of 400 to 500 r.p.m.; with the governor not in operation due to the vehicle being stationary; and with thethrottle valve supplying no oil pressure through line 113 to the throttle modulator valve, the following operation occurs. Oil from the pump 64 is supplied through the line 96 to the bore f the cut-oft" valve 120 and thence through line 128 to a port in the body of the throttle modulator valve 102 at which location further ow is blocked. Simultaneously oil passes through the branch line 98 from line 96 to the bore of the low speed regulator valve 80 between lands 82 and 84 thereof and from this bore through the line 100 to the bore of the throttle modulator valve 102 between lands 104 and 106 thereof. The oil entering this bore can continue through the line 60 to the left end of piston 36 to the converter stator, exerting a force thereon to move this piston 36 to the right against spring 38 to increase the angle of the blades. Full pump pressure, however, is not fed in the path just described to piston 36 due to the action of the low speed regulator valve 80. A part of the oil entering the bore of this valve between lands 82 and 84 continues through the diagonal channel 88 to the left end of channel 84, there to exert pressure to move the valve 80 to the right against the resistance of spring 86. As soon as the pressure developed beyond the low speed pressure regulator valve exceeds the preloaded strength of spring 86, i.e., 28 p.s.i., this pressure is reflected on the left end of land 84 and will move the valve 80 to the right `against spring 86. Such movement causes a partial closing of the port connected to line 98 and at the same time causes a partial p.s.i. on the low speed regulator which passage permits oil to be exhausted to reduce the pressure thereof. When the pressure inline and other parts of the system in communication therewith falls below the preloading of spring 86, this spring serves to return the valve 80 to the illustrated position completing a cycle of regulation. So long as the4 governor 70 is inactive the regulator valve 80 operates to regulate the delivered pressure therefrom to a maximum( value of slightly in excess of the strength of spring 86, that is, slightly in excess of 28 p.s.i. This regulated pressure of the order just mentioned is fed to the piston 36 and, with the pump 10 at idling speed, the hydraulic pressure applied to piston 36 is sucient to move this piston to the right thereby changing the angle of the blades 50 from low to high. As is known, increase in the angle of the blades reduces or eliminates the tendency of the vehicle to creep when the engine is idling. So long as the pump 10 is rotating at idling speed, the velocity of the liquid circulating in the converter is not high enough to exert a force sufliciently great to move the blades 50 to low angle. Using the figures before mentioned, it will be seen that during idling a hydraulic pressure of the order 28 p.s.i. or slightly more is supplied to the piston 36 to oppose the pressure of spring 38 (10 p.s.i.) and the effect of the velocity of the circulating liquid in the converter. The blades `therefore will be held in a relatively high angular position so long as idling speed of the pump 10 is not exceeded.

At the same time that liquid is supplied to the piston 36 by way of the bore of the throttle modulator valve 102, some of this liquid passes through the diagonal channel to the right of Valve 102 there to aid spring 108 in holding the valve 102 in the position shown. This hydraulic pressure combines with the spring pressure to create a total of the order 63 p.s.i. acting on the valve 102 but this force performs no useful function during idling or even during some throttle valve conditions which will be described later.

Light throttle acceleration If it is desired to accelerate the pump verter to such a degree as to cause a drive by the turbine 18 of the converter, such acceleration of the converter pump can be carried out with various throttle openings. If a light throttle opening is employed, the following action will take place so long as the pressure delivered by the throttle valve 112 through line 113 to the left end of land 106 does not exceed 35 p.s.i. Assuming that the pump 10 is accelerated under light throttle and a vehicle driven bythe converter is placed in motion, the following occurs. Slow speed regulator valve 80 which had been regulating pressure to the order of 28 p.s.i. during idling of pump 10 continues its function of regulating the pressure supplied to piston 36 but this regulation is influenced by pressure supplied by the governor 70 through line 72 to the left end of the governor plug 92. Since this governor pressure increases in accordance with the speed of the vehicle, the pressure delivered thereby will act to reduce the pressure delivered through the line 100. In other words, if the governor pressure has an effective force of l0 p.s.i. at a particular instant, the pressure regulated by the valve 80 will then fall to 18 instead of 2,8 p.s.i. This pressure may not be suiicient to hold the piston 36 in its high blade angularity position since the pressure of 18 p.s;i. is opposed not onl'y'by the spring 38 but is also opposed by the velocity of the circulating liquid in the converter. Consequently, the present arrangement makes possible a start of operation in which the blades 50 are almost immediately subjected to forces moving them from their high angularity position to an intermediate position. The illustrative governor pressure just given is merely as an example and is not indicative of any particular phase of operation. However, in practice it has been found that with a light throttle opening 10 of the conf -"since 'throttle valv line 160 and in line 60 drops -b on the right end of valve 102 will be less ypass thro act on piston 36 vexceeds fajsagero ff'apiidwithtthe' converter pump :.10 "being accelerated; the t almostimmediate result 'is'the positionin A A nfianinterme'diate angular position sothatthe vehicle "can be'smoothly accelerated and then as the -velocity Vof therfluidfin the converter: furtherincreases and as'fthe fregulatedfpressure delivered by valve'y decreases, these *'bladeswillbe restored in gradual mannertorlovyangu- `lilairitypositionjvvithout any jerk or-suddenmovement `V`Vthereofof a nature-thatcan be-felt in the vehicle." p

The regulation action of valve-Silcontinuesuntil'the ngovernor'pressureidelivered, throughfline 72 exceeds 28 Ap;s.i.r at `which time the plug 92y -Will force valveftltohe 'right causing llaud 84 to'close ,thet'portrconnected tosup- 'ply line-98 and to open fully the `port connected'tolt-he p 'exhaust passage140 so thatoil in line Ilt, line 66 and in "the'eyliuder of'piston will'be exhausted assuringposi- "ftioningof blade p 'l cation' angular position.

s "56 'in' their 'j minimurn torque` multiplivDuring such. lightthrottle 'posiftion" 'thel throttle 'modulating `valve llremains" stationary e pressure delivered throughline 113 'is neverfhigh enough to move valve 102 to Ltheright jaga'inst Spring 108.

z Mediumy throttle acceleration Assume. again 4that vthe converter. "is to be .accelerated lfromidling condition-but with a vmedium throttlesuchfas .wouldcause the Vthrottle valve- 112 to supply-athrottle valve pressure 55 p.s.i. to the left end of land 106. fAs .thezacceleration is Hinitiated this vthrottle v valve pressure ..6h55 psi. ,isnot sufficient to move thethrottle modulator k{.valve :102 to :the right against `Spring 1108y and -t-hefhy- ,drauliopressureaiding thisspring 'since these'tWo -pres- .,sures combined-are oftheorder of'63 psi. Underzt-hese .fashion as before described with la gradual-reduction in .thepressure supplied by the Valve 8010 the lineltland ,thence tothe lineri.V However,Whenftherpressureiu elovv p.s.i; the combined pressure acting than 55 p.s.i. which is thethrottle Valve pressure of this example. When thisoceurs the throttle'valvelpressure will-.move Vvalve 102 to theright closingtt'heportcon- .nectedto linej-ltltl and opening the portconnected to line 128. Fullpump pressure in linel 128.*at thisftime Will then venterthe bore of the valve 102 and somerof theoil will continuerthrough line 66 to the piston -36 and some'will ugh the diagonal channel 110 into the -chamber Yof spring |1018. As soon as the pressure thus'developed .inlthe systembeyondthe valve 102 andparticularly to 20 p.s.i.,1the -eecttthereof in the chamber of spring 108 and acting on'the right end of` land .104 of valveilil?. combined with spring 163 will kbe Vto .mover-'this valve to theleft against throttle valve pressure :of 55;p.s.i. Movement to the originalposition .causes =t he oil of the pressureof slightly over `2i}'p.s.i.to be ef- .fective in line 16@ to i :8010 v.exhaust the same if such valve has not'been .moved to 4the full exhaust position. For example,'if the valve :80 is operating A order of l0,p.s.i.twhe n valve 192 has been. moved to the 4right,.the Ysudden influxf of oil into this line100 fat 20 -;p.s.i. kwill merely be reilectedback to valvei80,'fthereto .-be exhausted. if the valvet) has been moved by goveryrronpressure to a/position fully closingthe port connected ,to lin'e98 and fully opening the port connected to exhaust t-passagejld, the lin'e '.160 will serve merely as an exhaust 'Ihe; just @described action of valvev 102 'therefore is'to i ycausefthe ,delivery by .this valve linto linel 60 andfthen sito piston 36 of; av pressure which'corresponds'tobtheimposed:throttle` valve ypressure minus VtheLpreloading"of :spring,.108. With the examplejust given,ie.,-a"throttle valvez'pressure-of 55y p.s.i., it will be'seenl-'that the imaxi- ,-rmumrpressurethatcean bedelvered to the piston 3'6'-Will circumstancesacceleration will be-rnitially 1n thewsame 5,35v imo* ,line-,iw and back. to p the *re n turn cause the action of valve to rdeliver pressure to line 100 tin the'y 'bel in the"order"f201p1s.i. `So 'longjasfthethrot'tle valve is 'held 'in` position'todeliver this pressure 'to thethrot'tle modulator valve, the A'modulated pressure' is applied to `piston 36 `holding the same ,in ian intermediate'torque f5 multiplicationposition overalonger period of time than during light lthrottle ope tluidcirculating inthe converter must increase suiciently to overcome the hydraulic pressure on piston'36 in excess `of that necessaryto 'balance the force of spring 38. In

`10 medium throttle position, therefore,'the'pump lcan accelerate to a considerably higher speed of revolution before the blades 50 are restored in a gradual manner to the low torque multiplication"angularity than `with alight Ythrottle acceleration. l5

y lWiz/1e throttle-acceleration 4'At any '.throttlejposition wherein the throttle valve 112 delivers apressureto lthethrottle modulator valvein ex-v cess of 63 p.s.i.,' the following takes place. If nthe vehicle 20 kis being acceleratedfrom rest'fwithfsuch -a throttlevalve position, the immediate effect V'thereof is to force the vthrottlemodulator valve102 to thefright closing `lthe port connected to the lineltlil and opening the port connected lto line'128. Pressuredelivered lby valve 102 through'line 60 to piston 36 willthen be apressure'equalito throttle v--valve pressure minus' the 35 p.s.i. preloadingl of `spring '5103. For exarnpleivith 90-lbs. throttle `valve pressure, V"thefvalvellll will regulaten the manner before described 'to cause'a delivered pressurein line 60 ot'55 p.s.i." -Such "higher pressure actingfonipiston 36 will holdiitin'the "high torque multiplication'-angularposition over. an extendedjperiod of operation. The'necessary exhaust for nvalve `fduring its regulating'actionegain is 'obtained -by impressing'the regulated'pressurefor excess pressure,

gulator Valve'80 which can relieve the excess pressure. `With a'pressureof 155 Jp.s.i. imposed onfthe pistouo, itfollows'thatthe blades i 5i)- can be moved to the Alovv'torque multiplicationlposi'- Ition only vvhen thevel'ocityo Vthe liquid beingcirculated iO-in the converter'has attained a highdegrree. It is even possible that with such a pressure, the'blades "W'illbeheld against return to low angular, position until the vehicle has reached aspeed at which the cut off Valve 120 functions If this' valve is calibrated kto operateat -a vehicle speed of say 58 m.p.h. when.'V governor pressure in, line74 is representative of'that speed, the valve-'120 t `Will be moved to'theleft against spring 126 Vclosing the Qport connected' to supply line96 and connecting the port fof line`128 tof the exhaust passage 159. This latter con- 'dition immediately exhausts all liquid `being suppliedto piston 36 so that the blades are promptly moved to low 'angular position by the combined action of springSS and .,the'circulating fluid. in the converter. lt the throttle is held more or less constant and the vehicle speed decreased below say 54 mph., spring 126cmV then act to more the `cut off valveV 126 to the right, restoring it to the illustrated position whereupon thethrottle modulator valve lili. will ,'again function in 'themanner beforerlescribed. 'it will be noted that land122 of ValVeJtZ() is larger thanland 50 124`so that these unbalanced areasof thetwo' lands Vcause a diierent upshift and downshift. point. With oil in the Abore between lands 122 and'124,'greater pressure isexerted' to-hold the valve to 'the right than .when oil isexv hausted from Vthis bore. The spring 'lltherefore can be calibrated for whatever speed of operation is desiredand likewise the hysteresis effectoifthe two lands can be calculated for a desired speeddiicrential.

Full throttle acceleration throttle'can be movedso'that'throttle valve 112 delivers y maximum throttle valve pressure to the vali/e162. With the examples 'before'.given, itwill be apparent that throttle "I5 -valvetpressurey being pump pressure, will be on the order ration since the velocity of the Y of 130 p.s.i. so that the valve 102 will regulate or modulate a pressure to be delivered to piston 36 in the order of 95 p.s.i., the diterentiai between the throttle valve pressure and the spring 108. Assuming that the vehicle is being accelerated from idling or at rest, it follows that the immediate supply of 95 lbs. pressure to the piston 36 will compel the blades 50 to multiplication angular position as the pump 10 is accelerated and that there will be no delay in the assumption of this angular position, Consequently acceleration can be immediate and of the maximum value. At full throttle operation the modulated pressure to piston 36 will continue and will be high enough to hold the blades in high angular position until the vehicle reaches a speed at which time the cut off valve 120 will operate..

A highly important advantage resides in utilizing the controls just described, particularly for wide or full throttle operation, since positioning of the blades in the high angularity position and maintaining the blades in such position so increases the torque absorption capability of the converter as to raisethe stall speed of an engine driving the same to a speed above that speed at which auto-ignition has been found to occur.

The torque multiplication ratio of the converter can be increased at any time during the operation of the converter below the speed at which cut oiT valve 120 operates by merely adjusting the throttle so that the throttle valve HL2 will deliver a pressure which can cause the before described operation of the throttle modulator valve 02. If the vehicle is cruising at a speed below the cut on speed with the throttle at other than full throttle position and with the blades S in the low torque multiplication angular position or some intermediate position, a movement of the throttle to cause throttle valve 112 to deliver maximum pressure will immediately result in changing the angularity of the blades to the high torque multiplication position. In this fashion the driver of the vehicle is able to determine the operating condition of the converter over a wide range of vehicle speed. Similarly a relaxation of the throttle pressure delivered by valve 112 will hasten the automatic movement of the blades Si! to low angle position from high angle position or any intermediate position.

It is to be understood that the invention is capable of modification, that the particular values of preloading of the springs are merely illustrative and that other changes in calibration can be made all W'thin the scope of the following claims.

What is claimed is: Y

1. In a transmission for a vehicle, a torque converter having bladed pump and turbine elements and a reaction element, said reaction element having blades movable from a high torque multiplication angular position Vto a low torque multiplication angular position, a movable member connected to said blades to control the position thereof, means exerting a constant biasing force on said movable member to move said blades to the low torque multiplication angular position, said blades being so mounted in said reaction member that the force upon said blades of the liquid circulating in said converter assistssaid biasing means, a source of fluid under pressure, and a pressure regulator valve for regulating and delivering pressure from said source to said movable member to oppose said biasing means thereby to move said blades toward the high torque multiplication angular position during relatively slow speed operation of said converter.

2. In a transmission for a vehicle, a torque converter having bladed pump and turbine elements and a reaction element, said reaction element having blades movable from a high torque multiplication angular position to a W torque multiplication angular position, a movable member connected to said blades to control the position thereof, means" exerting a constant biasing force on said movable member to move said blades to the low torque be held in the high torqueto said movable member to itl multiplication angular position, said blades being s mounted in said reaction member that the force upon said blades of the liquid circulating in said converter assists said biasing means, said force increasing with increase in speed of rotation of said pump element, a source of Huid under pressure, and a pressure regulator valve for regulating and delivering pressure from said source oppose said biasing means thereby to move said blades toward the high torque multiplication angular position during relatively slow speed operation of said converter.

3. In a transmission for a vehicle, a torque converter having bladed pump and turbine elements and a reaction element, said reaction element having blades movable from a high torque multiplication angular position to a low torque multiplication angular position, a movable member connected to said blades to control the position thereof, means exerting a constant biasing force on said movable member to move said blades to the low torque multiplication angular position, said blades being lso mounted in said reaction member that the force upon said blades of the liquid circulating in said converter assists said biasing means, a source of uid under pressure, a governor for regulating variable pressure, and a pressure regulator valve for regulating and delivering pressure from said source to said movable member to oppose said biasing means thereby to move said blades toward the high torque multiplication angular position, said pressure regulator valve being acted upon by variable pressure from said governor for reducing the pressure delivered to said reaction element from said regulator valve as the pressure from said governor increases.

4. In a transmission for a vehicle, a torque converter having bladed pump and turbine elements and a reaction element, said reaction element having blades movable from a high torque multiplication angular position to a low torque multiplication angular position, a movable member connected to said blades to control the position thereof, means exerting a constant biasing force on said movable member to move said blades to the low torque multiplication angular position, said blades being so mounted in said reaction member that the force upon said blades of the liquid circulating in said converter assists said biasing means, said force increasing with increase in speed of rotation of said pump element, a source of fluid under pressure, a governor for regulating variable pressure, and a pressure regulator valve for regulating and delivering pressure from said source to said movable member to oppose said biasing means thereby to move said blades toward the high torque multiplication angular position, said pressure regulator valve being acted upon by variable pressure from said governor for reducing the pressure delivered to said movable member from said regulator valve as the pressure from said governor increases.

5. In a transmission for a vehicle, a torque converter having bladed pump and turbine elements and a reaction element, said reaction element having blades movable Afrom a high `torque multiplication angular position to a low torque multiplication angular position, a movable member connected to said blades to control the position tliereorneans exerting a constant biasing force on said movable member to move said blades to the low torque multiplication angular position, saidblades being so mounted in said reaction member that the force upon 'said blades of the liquid circulating in said converter assists said biasing means, a source of duid under pressure, a governor for regulating variable pressure and a pressure regulator valve for regulating and delivering pressure from said source to said movable member to oppose said biasing means thereby to move said blades toward the high torque multiplication angular position, said pressure regulator valve being acted upon by variable pressure from said governor for reducing the pressure assaggio s l1 delivered .to said movablemember from said regulator vvalve as the pressure from said governor increases, said regulator valve exhausting pressure from -said movable member when said pressure from said governor acting thereon exceeds avpredetermined maximum.

6: In a transmission for a vehicle, a torque converter having bladed pump and turbine elements and areaction element, said reaction element having blades movable from a high torque rnu'iltiplication angular position to a low torque multiplication angular position, a movable member connected to said blades'to control the position thereof, means exerting a constant biasing force on said movable member to move said blades to the low torque multiplication angular position, said blades being so mounted inV said reaction member that the force upon said bladesof the liquid circulating in Said converter assists said biasing means, said force increasing with increase in speed of rotationof said pump element, a source ofuid under pressure, a governor for regulating variable pressure, and a pressure regulator valve for regulating and "delivering 'pressure from said souce to said movable member to oppose said biasing means thereby to move said blades toward the high torque multiplication angular position, said pressure regulator valve being acted upon by variable pressure from said governor for reducing the pressure delivered to said movable member from said regulator valve as the pressure from said governor increases, Asaid regulator valve exhausting pressure from said movable member 'when said pressure from said governor actingthereon exceeds a predetermined maximum.

7. in a transmission for a vehicle, a torque converter having bladed pump and turbine elements and a reaction element, said reaction. element having blades movable 'trema high torquemultiplication angular position to a L,ow torque lmultiplication angular position, a movable member connected to said blades to control the position -thereof, means exerting a constant biasing force on said 'movable member to move said blades to the low torque "multiplication angular position, said blades being so mounted in said reaction member that the force upon said blades of the liquid circulating in said converter assists said biasing means, a source of Viluidunder pressure, Ya manually operated valve for regulating variable pressure,

a governor for regulating variable pressure, a pressure. regulating valve for regulating land delivering pressureV kfrom said source to said movable member to oppose said biasing means thereby'to move said blades toward the 'high torque multiplicationY angular position, said pressure regulating valve being acted upon by variable pres- 'surelfrom said governor for reducing the pressure de- 'livered to'said movable member, a modulator valve interposed between said regulating valve and said movable member, a connection between ksaid 'modulator valve and said source, said modulator valve being subject to .pres` sure from said manually operated valve for modulating thepressure of liu'id to'said movable member in accordance with the pressure from said manually operated valve, and a valve intermediate said source of pressure and 'said modulator valve for interrupting the flow of fluid vfrom Asaid source to said modulator valve upon the attainoia p `edetermined delivered pressure by said governor.

8. ln a transmission for a vehicle, a torque converter 'having bladed pump and turbine velements and a reaction r ielenient, said reaction element having blades movable fromja high torque multiplication Vangular position to a :low torque multiplication angular position, a movable Amember connectedto said blades to control the position thereoffnieans constantly exerting a biasing force on said .movable member to move said blades to the lowtorque' Y multiplication yangular position, said blades being so mounted in said reaction member that the force upon said 'i blades 'ofthe liquid circulating in said converter assists said biasing means, a source of uid underpressure, a "'manually'operated valve for regulating variable pressure,

a governor for regulating variable pressure, a pressure regulating valve lfor regulating and` delivering .pressure from. said source to said movable member to oppose said biasing means thereby to move said blades toward the high torque multiplication angular position, said pressure regulating valve being acted upon by variable pressure "from'said governor for reducing the pressure delivered to said movable member, a modulator valve interposed 'between said regulating valve and said movable member, a connection between said modulator valve and said source, said modulator valve being subject to pressure from said manually operated valve for modulating the pressure of fluid to said movable member in accordance with the pressure from said manually operated valve over a range of relatively high pressure from said manually operated valve, and a valve intermediate said source of pressure and said modulator valve for interrupting the flow Vof iiuid front said source to said modulator valve upon the attainment of a predeterminedv delivered pres- Ysure by said governor.

9. ln a transmission for a vehicle, a torque converter 'having bladed pump and turbine elements and a reaction element, said reaction element having blades movable from a high torque multiplication angular position to a low torquemultiplication angular position, a movable' member connected to said blades to control the position thereof, means constantly exerting a `biasing force on said movable member to move said blades Vto the low torque'multiplication angular position, said blades being so mounted in said reaction member that the force upon said blades of the liquid circulating in said converter l'assists"said'biasing means, a source of iluid under pressure, a manually operated valve for regulating variable pressure, a governor for regulating variable pressure, a pressure regulating valve for regulating and delivering pressure from said source to said movable-,member to Voppose said biasing means thereby to move saidblades towardrthe high torque Vmultiplication angular position, said pressure regulating valve being acted upon by variable pressure from said governor for reducingthe pressure delivered to said movable member, a modulator valve interposed between said regulating valve and said movable member, aconnection between said modulator valve 'and said source, said modulator valve being subject to pressure from said manually operable valve for modu- "lating"'the pressure of liuid to said movable member in accordance with the pressure from said manually operated valve over a range of relatively high pressurefromsaid manually operated valve, and a valve intermediate said source of pressure andsaid modulator valve upon the attainment of a predetermined delivered pressure by said governor, said modulator Vvalve being soV Vcalibrated as 'to be inoperative to modulate pressure from said source over a range of relatively low pressure from said manually operated valve.

lO. Inj-a transmission for a vehicle, a torque converter having bladed. pump, turbine. and reaction `elements,'-one of said elements havingthe blades thereof movable' from a high torque multiplication angular position to a low torque multiplication angular position, a movable memiber connected tofsaid blades to controlV the position thereof ,means exerting a biasing forceonsaidmovable member to move said blades to the low torque multiplication angular position, a source of fluid under pressure,a

. governor forregulating variable pressure, anda pressure regulating valve for regulating and delivering pressure --fromsaid source to said movable` member toopposesaid Y biasing means thereby to move said blades toward the imlhigh torque vmultiplication angular position, said pressure fregulating val'verbeing acted uponVV by variable pressure from lsaid governor for reducing the pressure delivered VVto` said movablefmember as governorrpressure increases Athereby -to cause said movable blades tofbe moved to i the inw-torque multiplication angular lposition.

11. In a transmission for a vehicle, a torque converter having bladed pump, turbine and reaction elements, one of said elements having the blades thereof movable from a high torquelmultiplication angular position to a low torque multiplication angular position, a movable member connected to said blades to control the position thereof, means constantly exerting a biasing force on said movable member to move said blades to the low torque multiplication angular position, a source of iluid under pressure, a manually operated valve for regulating variable pressure, a governor for regulating variable pressure, a pressure regulating valve for regulating and delivering pressure from said source to said movable member to oppose said biasing means thereby to move said blades toward the high torque multiplication angular position, said pressure regulating valve being acted upon by variable pressure from said governor for reducing the pressure delivered to said movable member, a modulator valve interposed between said regulating valve and said movable member, a connection between said modulator valve and said source, said modulator valve being subject to pressure from said manually operated valve for modulating the pressure of iluid to said movable member in accordance with the pressure from said manually operated valve, and a valve intermediate said source of pressure and said modulator valve for interrupting the flow of uid from said source to said modulator valve upon the attainment of a predetermined delivered pressure by said governor.

12. A power transmission comprising in combination a hydrodynamic torque converter which circulates liquid through rotatable impeller, turbine and reaction elements, one of said elements having blades each of which is movable from a position making a high angle to a position making a low angle with a plane determined by the blade and the axis of rotation of the elements, an output member driven by the converter, a control member which determines the angular positions of the blades, means constantly urging the control member to hold the blades in low angle, said movable blades being so mounted in their rotatable element that the force of circulating liquid also urges the blades toward low angle, a source of uid under pressure which is operative whenever the impeller is rotating to maintain pressure sufcient to move the control member to high angle, and means responsive to rotation of the impeller below a predetermined speed for establishing communication between the source and the control member to urge the blades toward high angle, said last-named means being responsive to rotation of the output members above a predetermined speed for disconnecting the source of pressure from the control member.

13. A power transmission comprising in combination a hydrodynamic torque converter which circulates liquid through rotatable irnpeller, turbine and reaction elements, one of said elements having blades each of which is movable from a position making a high angle to a position making a low angle with a plane determined by the blade and the axis of rotation of the elements, an output member driven by the elements, a control member which determines the angular positions of the blades, means constantly urging the control member to hold the blades in low angle, a source of fluid under pressure which is operative whenever the impeller is rotating to maintain pressure suicient to move the control member to high angle, and means responsive to rotation of the impeller below a predetermined speed for establishing communication between the source and control member to urge the blades toward high angle, said last-named means being responsive to rotation ot the output member above a predetermined speed for disconnecting the source of pressure from the control member.

14. A power transmission comprising in combination an input shaft connected to an output shaft through a hydrodynamic torque converter which circulates liquid through rotatable impeller, turbine and reaction elements, one of said elements having blades each of which is movable `from a position making a high angle to a position making a low angle with a plane determined by the blade and its axis of revolution, a control member which determines the angular positions of the blades, means constantly urging the control member to hold the blades in low angle, said movable blades being so mounted in their rotatable element that the force of circulating liquid also urges the blades toward low angle, a rst source of fluid under pressure, a regulator valve normally delivering a substantially constant pressure from said. iirst source, means for conducting pressure fluid from the regulator valve to the control member during slow rotation of the impeller to urge the blades toward high angle; a governor which is a second source of pressure which varies with the speed of the output shaft, means associated with the pressure regulator valve for reducing the pressure delivered by the regulator valve, and means for conducting pressure iluid to the pressure reducing means from the governor to reduce the pressure on the control member as the speed of the output shaft increases.

15. A power transmission comprising in combination an input shaft driven by an engine controlled by a throttle, the input shaft being connected to an output shaft through a hydrodynamictorque converter which circulates liquid through rotatable bladed impeller, turbine, and reaction elements, one of said elements having blades each of which is movable from a position making a high angle to a position making a low angle with a plane determined by the blade and the axis of rotation of the elements, a control member which determines the angular positions of the blades, means constantly urging the control member to hold the blades in low angle, a source of tiuid under pressure, a regulator valve which normally maintains substantially constant the pressure of the source, means for conducting pressure fluid from the source to the control member to urge the blades to high angle, means responsive to the speed of the output shaft for reducing the pressure on'the control member, and means responsive to increasing opening of the throttle for increasing the pressure on the control member.

Cited in the tile of this patent UNETED STATES PATENTS 2,122,169 Wilson lune 28, 1938 2,727,360 Kelley u Dec. 20, 1955 FORETGN PATENTS 444,171 Great Britain Mar. 16, 1936 UNTTTD STATES TATENT OTTTCT CERTIFICATE 0F CORRECTICN Patent No.. 2,932,940 April 191, 1960 Bruce IVL, Edsell ei al.,

It is herebj'r certified that error appears in the-printed specification of bhe above 'numbered patent requiring correction and that the said Letters Paten-b should read as correo-bed below.

Column 12 line 50, after "valve" interrupting the flow of fluid from sai modulator valve insert for d source to said Signed and sealedi this 22nd day of November 1960I (SEAL) Attest:

KARL H. AXLINE Commissioner of Patents 

